A Core Center for Musculoskeletal Disorders will be formed at The University of Pennsylvania to provide critical resources for established and new investigators, from different disciplines, to address multidisciplinary research problems in "Musculoskeletal Tissue Injury and Repair". The aims of this Center are to enhance and advance the research productivity of investigators in Musculoskeletal Tissue Injury and Repair by developing: 1) three critical research core facilities that cross disciplines and hierarchies, 2) a pilot and feasibility grant program for new and established investigators, and, 3) educational, training, and research enrichment programs for the musculoskeletal community. The overall goal of the Core Center is to promote a cooperative interaction among investigators in a manner that will enrich the effectiveness of ongoing research and promote new research. Close collaboration and cooperation among investigators from a wide range of disciplines will be actively promoted and fostered. The musculoskeletal research programs at the University of Pennsylvania are quite broad, diversified, well recognized, and well funded as described in this proposal. In particular, the environment at the University of Pennsylvania is generally outstanding for independent and collaborative research and many examples of multidisciplinary collaborations are evident. In designing and developing Research Cores, we desired facilities that would either allow investigators to conduct their research more efficiently or more effectively or would allow investigators to perform studies that could not currently be performed due to lack of expertise or centralized funding. We also desired cores that would likely attract new investigators to musculoskeletal research problems by offering important and novel services and assays. We identified a need for cores in the areas of Microarrays, Structure Function Biomechanics, and Small Animal Imaging. These three areas were specifically chosen to build on existing expertise and structures at the University for efficiency and effectiveness of activity. As can be seen from the Research Base descriptions, each of these cores will not only be used by several investigators for existing projects, but will also serve as a new capability for many investigators interested in these approaches and technologies.